Hi all,

I am looking at the importance of maternal unemployment for child health in a dataset which tracks children from birth till age fifteen at five year intervals.

I have used the zanthro package for egen to create child BMI's at 9 months, as below.

Code:
egen ba_who1 = zanthro(O_babybmi_y0,ba,WHO), xvar(S_age_months_y0) gender(S_babygender_y0) gencode(male = 1, female = 0)  ageunit(month) gestage(S_gestationalage_y0)

egen ba_uk1 = zanthro(O_babybmi_y0,ba,UK), xvar(S_age_months_y0) gender(S_babygender_y0) gencode(male = 1, female = 0)  ageunit(month) gestage(S_gestationalage_y0)
I would like to use the zbmicat() function to categorize children according to body mass index (weight/height2) as normal weight, overweight, or obese. However, the help file describes that zbmicat categorizes children and adolescents aged 2–18 years. The children in wave 1 of this study are 9 months old. I know that it is not best practice to categorize BMI at such a young age, however I would still like the option of including this first wave of BMI in my analysis and describing the pitfalls therein to a reviewer.

My question is, would the standard approach below be appropriate, or does the zbmicat draw from growth tables that cannot be applied to a 9 month old?

Code:
egen ba_cat1 = zbmicat(O_babybmi_y0), xvar(S_age_months_y0) gender(S_babygender_y0) gencode(male = 1, female = 0)  ageunit(month)
Very best,

John

References:

Zanthro: https://www.stata-journal.com/sjpdf....iclenum=dm0004

Zanthro update: https://ageconsearch.umn.edu/record/...t_dm0004_1.pdf